For example:
A character without body development has a single hit to each location, such a character is limited to a maximum of two hits per location and therefore can never gain through any means more than one more hit per location.
A character with body development has two hits per location and is therefore limited to a maximum of four hits per location.
A level one spellcaster or incantor can have a maximum of eight first level spell cards per day.
The protective value of armour is limited to double its base value. The protection value of light armour can be increased by a single point, that of medium by two points and that of heavy armour by no more than three.
If you increase the number of basic character points you have spent on either of these skills, the rule of double will apply to the new total.
For example, if you spent three basic character points on ritual magic last year, the maximum number of personal ritual points you could have had would have been six. If you decide to increased the number of points you spend on ritual magic to six for the next year's events, the maximum number of personal ritual points you can have will increase to twelve.
Addenda:
If you are in any way unsure as to whether or not the rule of double will effect your character please check with asenior referee.